Apparatus for the continuous shaping of tubes from a web of paper or the like



April 29, 1958 H. s. v. JRUND I 2,832,271

APPARATUS FOR THE CONTINUOUS SHAPING 0F TUBES FROM A WEB OF PAPER OR THE LIKE 6 Sheets-Sheet 1 Filed Dec. 26 1951 H. S. V. JRUND APPARATUS FOR THE CONTINUOUS SHAPING OF April 29, 1958 TUBES FROM A WEB `OF' PAPER OR THE LIKE 6 Sheets-Sheet 2 Filed Dec. 26, 1951 April 29, 1958 H s, v JRUND 2,832,271

APPARATUS FOR THE CONTINUOUS SHAPING OF TUBES FROM A WEB OF' PAPER OR THE LIKE Filed Deo. 26, 1951 6 Sheets-Sheet 3 |l J6. Il 25 April 29, 1958 H. s. v. JRUND APPARATUS FOR THE CONTINUOUS SHAPING OF TUBES FROM A WEB OF PAPER OR THE LIKE 6 Sheets-Sheet 4 Filed D60. 26, 1951 H. S. V. JRUND APPARATUS FOR THE CO TUBES FROM A WEB OF' 5l 2,832,271 NTINUoUs SHAPING` oF PAPER 0R THE LIKE April 29, 1958 6 Sheets-Sheet 5 Filed Dec. 26, 19

Rigid JMW MJWVM@ April 29, 1958 H. s. v. JRUND 2,832,271

APPARATUS FOR THE CONTINUOUS SHARING OF TUBES FROM A WEB OF PAPER OR'THE LIKE Filed Deo. 26, 1951 6 Sheets-Sheet 6 nited States arent APPRATUS FOR THE CONTINUOUS SHAPING OF TUBES FRM A WEB F PAPER 0R THE LIKE Harry S. V. Jrnnd, Lund, Sweden, assignor, by mesne assignments, to Hermorion Ltd., Toronto, Canada Application December 26, 1951, Serial No. 263,358

Claims priority, application Sweden December 30, 1950 5 Claims. (Cl. 93m82) The present invention relates to an apparatus for continuously converting a web of a suitable fiber or foil material, e. g. paper, textile material, metal or articial resin foils or the like, into a substantially cylindrical tube or sleeve.

Apparatus of this kind is particularly useful in the packing industry, e. g. in connection with the production of bags having a straight bottom, pillow shaped or tetrahedral packages etc. Thus, an apparatus of the kind referred to may advantageously be used in combination with a tetrahedron shaping machine, for instance according to my copending patent application Serial No. 263,357 filed December 26, 1951, which issued as Patent No. 2,738,631.

The primary object of the invention is thus an apparatus for so bending a web as it is continuously withdrawn from a roll as to form a tube or sleeve and simultaneously sealing together the borders of the shaped open tube to form a longitudinal joint.

Another object of the invention is to guide the web during sha-ping in such a manner that the formation of creases, particularly in the longitudinal joint, is substantially avoided, since otherwise such creases would jeopardize the tightness of a package thereafter produced.

For attaining the above-mentioned objects and other advantages which will be obvious from the following description, the apparatus according to the invention consists in its principal parts of a turning-over or guide roller mounted in a machine frame and provided for the web to be bent to form a tube and, in spaced relation to said guide roller, an outer shaping sleeve in the form of a ring split along a generatrix and somewhat flattened along one of the cut-open edges, said shaping sleeve being so orientated relatively to the web lbeing shaped that the outer overlapping border of the latter will be guided along the flat edge portion of the shaping sleeve. Further, provided below the shaping sleeve are a gluing or heating device for applying glue or bringing adhesive contained in the web to a suitable sealing temperature, a device for pressing together the border zones loverlapping each other and provided with glue or brought to gluing temperature, and finally devices for feeding the web and the shaped tube through the machine.

Particularly in cases where the material from which the tube is to be produced has an insuicient stiffness or resilience, it may be suitable either to provide a brake acting on the web before it passes over the guide roller, so that the web will continually be under a tension increasing the stiffness or the resilience, or to provide guiding rods or a guide surface adjusted for the desired shape of the web and disposed between the guide roller and the shaping sleeve situated next to the guide roller. In certain cases, also a combination of these two expedients may be suitable` In order to render possible the step of pressing together the border zones overlapping each other a counterpressure Idevice within the shaped tube is also required. Such a device, preferably in the form `of apressure or fice counter-pressure roller, is suitably mountedin an inner sleeve carried by a holder arm fastened to the machine trame and passing through the wedge shaped opening between the longitudinal borders ofthe web being shaped,`

before these borders are brought into the overlapping position.

The invention will be described more in detail in the following with reference to the accompanying drawings4 which by way of example, but not in a limiting sense, illustrate one embodiment in which the web material employed is assumed to consist of thermoplastic mate.

rial or of a web of paper impregnated with a thermoplastic adhesive. i i

in the drawings: Fig. l is a perspective view of an apparatus according to the invention;

Figs. la-le are sections taken on correspondingly numbered lines in Fig. 1;

Fig. 2 shows a detail of the lower shaping elements as well as heating and compressing devices for the longitudinal joint; l

Fig. 3 shows the upper sleeve-likeshaping element, as,

viewed from above; Fig. 4 is a section through the with mounted pressure rollers;

Fig. 5 is a section through the heating element;

lower shaping `element4 Fig. 6 is a fragmentary perspective View, similar to; Fig. 2, of an alternative construction for the shaping ele-f ments, and the heating and sealing elements;4

Fig. 7 is a plan view of the upper shaping member',

of Fig. 6 as seen with the cover ring removed and turned counterclockwise by from the position shown in Fig. 6, the web being shown in horizontal section;

Fig. 8 is a side elevation of the shaping` element as seen partly in section on theline VIII-VIII of Fig. 7;

Figs. 9 and 10 are similar plan and `side elevations, respectively, of the lower shaping element, the section of Fig. 10 being taken on line X-X of Fig. 9;

Fig. l1 is a fragmentary vertical section` showing thel sealing mechanism et' the Fig. 6 construction;

Pig. l2 is a fragmentary horizontal section on line Xll-Xll of Fig. l1; and v Fig. 13 is a view taken on line 13-13 of Fig. 1. but drawn to a somewhat larger scale and showing the angular relationship between the sealing zones and the axis of the guide roller for the web material. r

ln the embodiment shown in Fig. l, reference numeral 1li designates a vertical machine frame which at the top-j carries a guide roll 12 for the web,e. g. a web of paper 14, from which a continuous tube 16 is 'to be shaped through a bending of the web to a cylindrical shape.

Preferably, the guide roller 12 is adjustably secured to the treme 1G in order to render possible a correct orientation of the longitudinal joint of the shaped tube 1'6 rela'- tively to the shaping, heating and compressing members which are described more fully in the following.

Provided for the shaping proper are in the embodi- Disposed between the two shaping sleeves 18 and Zllzis` a heating element 24, as shown in Fig. 5, formed witlr a slot 26 through which the outer overlapping.borderZSof V the paper web passes while being heated fromv both Sides.`

whereas the inner joint border 30 rubs against that surface Patented Apr. 29, 1958l `heating element 24 takes place electrically by means of r'esistancelelements inserted in the same and connectable :toa suitable source of current or to the supply network via' terminal screws 32, 34. I

Below the heating body 24 there is provided a pressure vroller 36 which, in the embodiment according t'o Fig. 2, is'fitted in a recess 37 Vinthe lower shaping sleeve 20. The pressure roller 36'is mounted on a lever 38 and is subjected to an urging pressure adjustable by means of a screw 40 and a spring 42 or the like. The shaping sleeves 18, as well as heating element 24 and the lever 38 are carried by a rod 44 which is secured to an attachment 46 extending from the machine frame 10.

' vThe attachment 46 `extends inwards through the wedge shaped opening between the borders 28 and 30 of the paper web, before said borders have been brought into the overlapping position, and carries a sleeve 48 extending vdownwardly into the formed tube, which sleeve may serve both as an inner guide and as a carrying member for an inner counter-pressure roller 50 (Fig. 4) cooperating with theouter pressure roller 36.

In the embodiment shown in Figs. 6 to 12, each of the shaping sleeves 18 and 20 of the embodiment above described has been replaced Iby a series of concavely spherical rollers 52, 54 carried by annular roller holders 56, 58, respectively..- In the upper shaping element, the two rollers v52a situated next to the joint yopening are not symmetrical but cylindrical, or approximately cylindrical, at 'their ends towards the joint opening in order appropriate- -l'yf'to shape and guide the edges of the web which do not 'yetentirely 'overlie each other. Of course it is, however, also possible,l by suitablyproportioning the size of the rollers, to give the rollers situated next to the joint opening an entirely cylindrical shape, in which event they are so arranged that their generatrix along which the engagement withthe web'takes place, coincides with the tangent to the curved generatrix along which the next adjacent concave rollers contact the web.

In the embodiment of the lower shaping element as shown in Figs. 9, 10, 11 and 12, it is suitable to provide an inner spherical pressure roller 60 convexly rounded to the curvature of the corresponding outer roller 54 to apply a sealing pressure over the entire width of the overlapped side edges of the web. 4The inner pressure roller 60 is carried by the sleeve 48 extending downwardly into the tube and is preferably yieldingly urged by a spring 42', in conformityto the outer pressure roller 36 of the embodiment previously described. Neither the pressure roller nor the counter-pressure roller is driven, but preferably both are mounted in ball bearings in order to reduce friction.

For feeding the web and later the tube through the machine there may be provided a number of driven feed rolls 62,-e. g. cooperating with abutment rollers 62 mounted in the lower end of the depending sleeve 48, in a manner similar to the mounting of the inner pressure roller 60 of Fig. 1l and preferably by means of ball bearings, see Fig. 1. The web 14 is drawn over the guide roller 12 and through the shaping elements by the feed rollers, and the upper shaping element is spaced a substantial distance below the guide roller to preclude heavy lateral stresses in the web as it is progressively bent from a linear to a circular cross-section. To avoid tearing or creasing of the web, the upper shaping member should be spaced from the guide roller by a distance equal-to several times the width of the web, for example about eight times the width ofthe web as shown in Fig. 1. I

lParticularly in cases where the web in itself has not a suicient elasticity or stiiness and where no brake is applied to the same to give it a tension for increasing the elasticity and the springiness, it is necessary to provide guiding means for the web between the guide roller 12 and the upper shaping element 18 of Fig. 2, the members 52, 56 of Fig. 6, respectively. This guiding means, which also serves to pre-form the web from a substantially at surface into one which is arcuate in transverse section, may be in the form of a guide surface obtained by slitting a cylinder along a generatrix, the cylinder having the diameter of the shaped tube and a length approximately corresponding to the distance between the guide roll 12 and the upper shaping element, the cylinder being then flattened at the top to receive the web as it leaves the guide roll 12, whereas the lower end retains its cylindrical shape. However, this guide surface need not `be uninterrupted but may be provided with longitudinal recesses or even, in most cases, may be replaced Iby two guiding rods 64 extending from points near the borders of the web immediately below the guide roller 12 to points more distant from the borders of the bent web at a level somewhat above the upper guide 18 or 56. For each guiding rod 64 there is provided an upper and a lower adjustable xing device 66 and 68, respectively, as a means of fastening the guiding rods to the machine frame and rendering possible an adjustment of their positions relatively to the web. As shown in Fig. l, the upper fixing device 66 comprises a horizontal rod 70 extending between the upright frame members 10 which supports laterally extending xed arms 71, 71. A pin 72 connected to one of the guide rods 64 is transversely adjustable in the arm 71 so as to make possible a lateral adjustment of this guide rod. In a similar manner a pin 72' connected to the other guide rod 64 is transversely adjustable in the xed arm 71 so as to effect a lateral adjustment of this guide rod. The lower fixing device 68 is similarly constructed, there being a horizontal rod 73 extending between the upright frame members 1,0, 10', arms 74, 74', secured to rod 73 and pins 75, 75' se cured to guide rods 64 and adjustably positioned in the arms 74, 74'.

On account of the shape which the web will assume between the guide roller 12 and the shaping elements, this web part obtains a certain stilness which, through a relative lateral displacement of the guide roll and the shaping elements in relation to each other may be utilized to control the contact pressure between the web and the guide roller. This contributes to retain that part of the web which is being shaped in place so that the path of the longitudinal joint through the machine is determined. As is evident from Fig. l the tube after leaving the lower shaping Ielement such as sleeve 20 is sealed at longitudinally spaced intervals along zones transverse to the axis of the tube, the successive seals being disposed in mutually perpendicular planes so as to establish packages having the shape of a tetrahedron. An apparatus for forming such seals is described and illustrated in my copending application Serial No. 263,357, led December 26, 1951. The mutually perpendicular sealing zones are indicated by numerals 78 and 79 in Figs. 1 and 13,. and a comparison between Fig. 13 and Figs. la-le shows that the axis 12a of the guide roller 12 which extends between the upright frame posts 10 is disposed at an angle to each of the sealing planes for the purpose of locating the longitudinal joint of the tube intermediate the ends of each sealing zone. If, for some reason, it is desirable to relocate the longitudinal joint, this may simply be effected by swinging the guide roller in the lateral direction. Preferably, the mounting devices of the guide roller are so designed that such a swinging motion becomes possible, while in addition either of the guide roller or the shaping elements are so mounted in means, not shown, as to be displaceable in the lateral direction for bringing about the contacting pressure of lthe web upon the guide roller.

I claim: 1. An apparatus for shaping a tube from a continuous web of flexible scalable material and sealing the tube assaavl along a continuous longitudinal joint comprising, an upright machine frame, a guide roller for the continuous web mounted at the upper end of said frame and in ficontact with that face of the web which is to form the inside surface of the tube, a pair of axially spaced shaping elements supported on said frame, said upper shaping element being spaced below said guide roller by a distance equal to at least several times the width of the web and having the form of a circuniterentially split ring with one end extending tangentially to provide a guide for the outer edge of the web which overlaps the other edge below said upper shaping element thus to form the tube, said lower shaping element being of annular form with an internal diameter equal to the external diameter of the shaped tube, said web at said upper shaping element and said tube at said lower shaping element being in sliding Contact with the inner surfaces of said shaping elements, means located between said upper and lower shaping elements to condition the overlapped edges of said tube for subsequent sealing together comprising a heatable body member provided with a slot extending longitudinally of the tube axis, said slot being arranged generally co-linear with said tangentially extending end of said split ring and serving as a guide means to receive the outer overlapping web edge and to effect heating 0f the same from both sides, the other edge of the web contacting the inner surf-ace of said heatable body as it moves longitudinally therealong, and pressure means located at said lower shaping element for bringing the overlapped edges of said tube into Contact with each other under pressure to effect the sealing thereof.

2. Apparatus as defined in claim 1 wherein each of said shaping elements comprises an arcuate array of rollers and a holder therefor, each said array of rollers establishing a continuous line of contact with the outside surface of the tube material throughout the width thereof.

3. Apparatus as defined in claim 2 wherein said pressure means comprises an inner pressure roller and one of said rollers of said lower shaping element acting as a counter-pressure roller for bringing the overlapped edges of the tube into pressure contact with each other.

4. Apparatus as dened in claim 3 and which further includes a holder extending inwardly from the machine frame through the `acutely angular opening formed between the edges of the web above said upper shaping element, and a sleeve carried by said holder and extending downwardly Within the tube being formed, said sleeve supporting said inner roller.

5. Apparatus as defined in claim l wherein said pres` sure means at said lower Vshaping element comprises an inner pressure roller located within said tube and contacting the overlapped edges thereof and an outer counter- `pressure roller located outside of said tube and contacting References Cited in the hie of this patent UNlTED STATES PATENTS 146,358 Quadling et al u Jan. 13, 1874 495,426 Murch et al Apr. 11, 1893 969,555 Neal Sept. 6, 1910 1,986,422 Zwoyer Jan. 1, 1935 2,105,273 Smith Jan. 11, 1938 2,145,636 Scharf Jan. 31, 1939 2,169,311 Widell Aug. 15, 1939 2,255,472 Quarnstrom Sept. 9, 1941 2,285,263 Fitch June 2, 1942 2,403,995 Peters July 16, 1946 2,484,075 Collins Oct. 11, 1949 2,491,048 Jenkins Dec. 13, 1949 2,607,696 Kunz Aug. 19, 1952 

